FOR almost a century, she was a ghostly and forgotten outline on the muddy seabed off our coast.

Now, a German U-boat which exploded in 1917 and became a deep-sea tomb for her 27-man crew has been found by a team of amateur divers.

They revealed the find yesterday, more than two months are stumbling across the wreck during a search for the U-boat.

Military historians have hailed the identification of UC-42 off Cork harbour as one of the most notable World War One discoveries in recent years.

The submarine was believed to be laying mines and taking part in attacks on British vessels when it exploded. The area saw intense maritime activity during the war -- including the sinking of the liner Lusitania with the loss of 1,200 civilian lives.

Irish divers and historians are now to liaise with the German Embassy in a bid to trace surviving relatives of the deceased. It is then hoped to stage a special remembrance ceremony in Cork.

No examination of the hull interior has been undertaken as yet but it is believed that the remains of the crew -- many of whom were in their late teens -- are still located within UC-42.

The amateur divers made the remarkable discovery in 28 metres of water off Roche's Point in Cork harbour on November 6 last.

Dive leader Ian Kelleher told the Irish Independent they had been examining the area for more than a year for traces of the submarine -- which naval historians believe exploded and sank on September 10, 1917.

The team of five divers -- Ian Kelleher; Niall O'Regan; Philip Johnston; Eoin McGarry and Timmy Carey -- had been searching for the wreck for a year when they "just struck lucky".

"Various people have looked for the wreck over the years with no success and we had been searching ourselves for 12 months or so," Mr Kelleher said.

"Then, myself and Niall were out about two miles off Roche's Point at the beginning of November and we just came upon the wreck. We noticed an unusual outline below us and we went down to check it out, and there she was," he said.

Fellow diver Philip Johnson said he hoped people would give UC-42 the respect it deserved as a war monument.

In a gesture of remembrance, the divers laid a special plaque and wreath at the site over Christmas.